Research on Ship Trajectory Tracking based on Nonsingular Fast Terminal Sliding Mode Control

To address the issues of chattering and slow convergence speed in traditional sliding mode control for underactuated ship trajectory tracking, this paper proposes a non-singular fast terminal sliding mode control method. Firstly, a virtual control law for lateral and longitudinal velocities is designed based on the lateral and longitudinal position errors of the ship. Then, an exponential reaching law is introduced to construct the non-singular fast terminal sliding mode controller, effectively solving the chattering problem in sliding mode control and improving the convergence speed of the system. Finally, the system's convergence within finite time is proved based on Lyapunov function and finite-time stability theory. Comparative simulation experiments demonstrate that the designed controller has good robustness and tracking performance, enabling the ship to quickly and accurately track the desired trajectory.